Researchers Sam Webb of SLAC (pictured) and Felisa Wolfe-Simon from NASA will present the next SLAC public lecture, “Life Redefined: Microbes Built with Arsenic.” The talk will begin at 7:30 p.m. on Tuesday, March 22 in SLAC’s Panofsky Auditorium.
Life can survive in many harsh environments, coping with challenges from extreme heat to the presence of deadly chemicals. However, life as we know it has always been based on the same six elements: carbon, oxygen, nitrogen, hydrogen, sulfur and phosphorus.
Now it appears that even this rule has an exception. In the saline and poisonous environment of Mono Lake, researchers have found a bacterium that can grow by incorporating arsenic into its structure in place of phosphorus. X-ray images taken at the Stanford Synchrotron Radiation Lightsource at SLAC reveal that this microbe may even use arsenic as a building block for DNA. The lecture will describe this discovery, which rewrites the textbook description of how living cells work.
Photo by Brad Plummer of SLAC